Seasonal influenza is a common infection, especially during winter. Every year strains of influenza (type A or B) circulate, giving rise to clinical consultations in primary care, episodes of hospital treatment (mainly in older persons and young children, but occasionally in middle aged adults), and deaths (mainly in the elderly). Treatment in primary care and hospital may be required due to the direct effects of influenza virus infection or its possible complications, most commonly secondary bacterial infection. Increases in primary care consultations for ILI and winter bed pressures are frequently associated with periods of known community influenza activity.
Pandemic influenza occurs when a new influenza virus subtype emerges which is markedly different from recently circulating subtypes and strains, and is able to:                infect humans;        spread efficiently from person to person;        cause significant clinical illness in a high proportion of those infected.        
Because the virus is novel in humans, a high proportion of the population will have little or no immunity, producing a large pool of susceptible persons; accordingly the disease spreads widely and rapidly.
Interferons have previously been proposed for either prophylactic or early stage intervention in the treatment of influenza, but with limited success.
Highly pathogenic influenza is a virulent form of influenza, such as H5N1, which leads to a rapid and high level of morbidity.
ILI includes seasonal influenza, pandemic influenza and highly pathogenic influenza.
We have now found a new method of treating individuals, particularly hospitalized patients, with lower respiratory tract illness that has developed during or following an ILI.